Punishment is prescribed on committing a crime because mere prohibition or mere command would not prevent people from acting against it.If there was no punishment, commands and prohibitions would become useless.If crimes against society go undetected and unpunished, the whole structure may be permanently impaired.It is far better that wrong-doers is punished and the rest of the society safeguarded. Hence, the saying of the Qur'an: "In punishment, there is life for you, O people of understanding..."(Al-Baqarah:179)